The present invention relates generally to exteriorly mounted rearview mirrors for vehicles and, more particularly, to power folding exterior rearview mirrors which fold between an operable position and a folded position in response to an electronic actuator, and to motors for positioning the field of view of exterior rearview mirror reflectors.
Exterior rearview mirrors are located on one or both sides of a vehicle to provide a vehicle operator with a view rearward and to either side of the vehicle. Many vehicles provide rearview mirrors which are foldable between an operable position, where the rearview mirror extends outwardly from the side of the vehicle, and a folded position, where the rearview mirror is folded alongside the vehicle. Conventional folding mirrors typically include a folding portion and a substantially fixed, non-folding portion, which is mounted adjacent to a side or side window of the vehicle. The folding portion pivots about a pivot axis defined by a pivot spindle, which is typically secured to the non-folding portion. While many of these folding mirrors may be manually folded between the operable and folded positions, or may move towards the folded position if impacted such as in breakaway mirrors, many vehicles now include power folding mirrors to facilitate pivoting of the mirror housing via a manual control within the vehicle or in response to an electronic signal.
Power folding mirrors and electrically operated mirror reflector positioning power packs typically include an electronic actuator, such as a conventional motor with a rotating output shaft. Moreover, powerfold actuators and mirror reflector positioning power packs/actuators commercially used utilize conventional armature motors which consist typically of an armature that is surrounded by a coil or coils (typically consisting of multi-wire windings) passing electrical current. The shaft of the motor turns by the actuator responding to electromagnetic fields generated by passage of electricity through the coil(s) of the motor. The need to accommodate at least an armature and coil(s) in the motor housing can lead to a relatively large package that in turn presents difficulties accommodating the actuator in the restricted space available in exterior rearview mirror assemblies. Thus, there is a need for a contact motor for such applications.
In powerfold mirror actuator applications, the motor is operable to rotate the output shaft, which engages multiple gears or worm drives which further engage the pivot spindle on the non-folding portion of the mirror. Rotation of the output shaft causes relative rotation between the motor and the spindle to thus pivot the mirror housing about the spindle. Such standard motors operate at relatively high RPMs and have a low output torque. Accordingly, multiple gears are required between the output shaft and the pivot spindle in order to generate enough torque to move the mirror about the pivot spindle. This results in multiple moving parts within the system, which may further result in increased weight and reliability concerns with respect to the mirror system.
Because there is relative movement between the folding portion and non-folding portion of the mirror as the mirror is folded inwardly toward or outwardly from the vehicle, difficulties may arise in routing an electronic cable or wiring from within the vehicle or door to the actuator positioned within the folding portion of the mirror assembly. Typically, corresponding openings or slots must be formed through one or both of the folding portion and the non-folding portion of the mirror assembly. This allows the cable to be routed from the non-folding portion into the folding portion such that the cable may move relative to one or both portions as the mirror is folded, with minimal interference with the movement of the folding portion of the mirror.